Several little comments to make....
Genesis isn't the name of the ship, it is the name of the project. They haven't named the first vessel yet. This has been big news off and on since they announced it a couple years ago. The ships will be around 220,000 Gross Tons, which is quite different from Displacement, which is how the U.S. Navy "weighs" their ships. Gross Tons is a measurement of volume and not dead weight. Thus, the aircraft carrier comparison is really apples and oranges. Cruise ship size is really the empty space and not the steel. And frankly, RCI took some liberties in proclaiming the Freedom class the largest in the world - at least according to some sources.
But beyond the technical issues and definitions, the Genesis class ships will certainly be huge even if they don't actually displace as much as a Nimitz-class carrier. The typical passenger load is to be in the mid-5000 range. This is the biggest secret at RCI. All the company's executives, officers, Cruise Directors, and others in senior positions have had to sign legally binding secrecy agreements. On the Freedom inaugural last year, Captain Bill Wright did tell us that buzz words around corporate were "Game Over".
We'll see. Of many considerations is how to handle that large a crowd, and not just for the ship. It could also pose problems for many Caribbean ports since that one ship is easily equal to two lesser vessels. One rumor on the Liberty two weeks ago was that RCI would have to make a dock at Labadee because the tender time for a Genesis class ship would be too much to handle.